Preparation and Technological Evaluation of Methacrylic and Polyacrylic Acid/Leucaena Gum as a Thickener in Printing Protein Fibre

Abstract

Polymethacrylic or polyacrylic acid/leucaena gum composites were prepared via grafting methacrylic acid monomers onto the galactomannan gum, isolated from leucaena seeds, using ammonium persulphate as an initiator. The rheological properties, in addition to the suitability of the composite for the direct printing of protein fabrics with acid or reactive dyes, were thoroughly investigated. It was found that polymethacrylic or polyacrylic acid/leucaena gum pastes are characterized by a non-Newtonian pseudoplastic behaviour; the apparent viscosity at a constant rate of shear depends on the neutralization and storage process. The prepared composites could be successfully used in printing wool and silk, regardless of the nature of the fabric. The K/S depends on the degree of neutralization of the composite employed as well as the storage time. The colour fastness properties to washing, rubbing and perspiration ranges between good to very good.